TechTales Blog

The other day I won the lottery at work. Yeah, you heard that right... I got chosen to work on a 2005 F150 equipped with a 5.4L 3valve engine with approximately 170K miles. 

Customer complaint was lack of power and dies after about 10 minutes.  I go and drive it and sure enough it has no power and is back firing through the intake.  I hook up IDS and I see all four cylinders misfiring on that one bank. Because of the symptoms, it was a pretty easy diagnosis.  A clogged converter on bank two.  I sell it to the customer and explain that we likely have a misfiring plug/coil that will need to be addressed after we replace the converter. I install it - the truck runs well, makes plenty of power, but the valve train is noisy when hot.  Downright scary. 

After some diagnostics, it becomes apparent the problem lies within the variable cam timing.  A simple oil pressure tests reveals a base engine oil pressure hot at idle only hitting 23psi.  We rip the front of the engine apart, the oil pan off, and replace all the timing components and oil pump.  You should have seen the oil sludge built up throughout this entire engine.  It took forever to clean the valve covers and front cover by hand.  There was literally an inch thick of oil sludge build up everywhere. We also sold the guy 8 new spark plugs as they were original and because of the horrible process of changing them he decided it was best for us to do it.  Another fixed vehicle on the road. Alright!

The other day I got the pleasure of working on a 2008 SuperDuty with a 6.4L under the hood.  All I am told when I am handed the ticket is that the customer wants the exhaust leak fixed. Wonderful. When it is started cold, you can hear the leak as well as see smoke coming from back by the firewall.  A quick peek through the fender opening reveals a exhaust manifold leaking but the rear pipes are also suspected.  In our shop, we pretty much pull the cab for a lot of different repairs.  Its rather easy.

I get the cab off, see the exhaust manifold leak but rear pipes look good.  I replace the exhaust manifold gasket, torque all the pipes down to spec, and reinstall the cab. I start it up and do not hear a leak, so I take off on a test drive.  The truck falls flat on its face whenever half throttle or more - so I wonder, what did I do?

The truck comes back into the shop, and I run IDS on it and get the dreaded P0088 code for excessive fuel pressure. Ford has a TSB referencing this code so I follow the repair procedures (a reflash of the PCM) then retest drive but experience the same results.  Sounds like the truck is going to need a new high pressure fuel pump.

We end of talking to the customer and find out that falling on its face was the issue all along.  He just assumed, and heard from other mechanic buddies, that an exhaust leak can cause that particular issue.  His exhaust leak did need to be repaired, but he could have saved valuable money in the long run.  In reality, this is a life lesson for both the dealership and the customer.  The customer should learn to have diagnostics performed to verify the cause, and the dealer should learn that the customer isn't always right.

The other day a couple brought to the shop a 2010 F150 equipped with the 6R80.  They just happened to have left the nearest dealer who painstakingly tried to fix it, but having failed, these customers were at our door. Their issue was their truck would not shift out of 3rd gear.  The previous dealer tried to install a new valve body and a megatronix assembly to no avail.  Not only did it not fix the problem, but they also went ahead and did a warranty repair claim to Ford for the valve body.

I drive the truck and sure enough, it starts out in third gear and never leaves it.  I hook up IDS and see the code for incorrect gear ratio for fourth gear.  I clear the codes and retest drive.  The truck starts in first, changes to second, then third, and attempts to go into 4th gear 3 times with no luck and then defaults to third gear. I dig through some workshop manuals and discover the only clutches that engage in 4th, 5th, and 6th is the overdrive clutch. I then remove the valve body assembly, and do a air pressure check on the hydraulic port for the overdrive clutch and hear a loud hissing sound.  Diagnosis is complete.

The transmission is removed from the vehicle and disassembled to find a broken piston cup.  Replace the effected parts under warranty, reassemble, an test drive.  All is good for everyone except the original dealer that did an improper repair - I am sure they will experience a chargeback.

For those who are unaware, Ford has recalled several thousand 2013 Ford Escapes with the 1.6L Ecoboost engine due to a fire hazard.  Simply put, the cylinder head overheats causing a stress crack on the back side of it above the exhaust and turbocharger assembly.  The crack allows oil to ooze out onto the hot exhaust system and down into the wiring looms for the crankshaft position sensor and turbocharger controls.  Hot exhaust plus fresh oil can lead to a fire.

In total, this recall is a 48-page novel.  Ford has decided in order to fix this issue, the technicians will install an "oil deflector" on the back of the cylinder head.  This deflector is specially designed to fit the curvature of the cylinder head and calls for the use of copper RTV to seal it.  This deflector shovels oil out an alternate route if a leak does happen to develop.  Obviously, this is just a band-aid as it does not address the actual cause of the concern.

The rest of the correction of the recall involves installing a new coolant level sensor (and associated wiring) to detect when the engine could be low on coolant, re-wrapping the wiring harness located behind the engine, poking holes in the under-body water deflector to allow spilled oil to drain, installing a new designed dipstick that supposedly does not leak as much, and removing a few rows from the active grill shutters. More importantly, on vehicles of certain build dates, the recall specifys that a lower temperature thermostat be installed.

Ford pays the technicians 6 hours to perform the recall.  The time frame seems lackluster at first because of the novel of instructions, but after doing a few of these it becomes quite the breeze. My first run through took approximately 8 hours, and the second time took just 15 minutes shy of 6 hours.

The Power Probe 3 is a very powerful, compact, and useful diagnostic tool. I would recommended that any technician specializing in electrical diagnosis pick one of these test probes up. The Power Probe III is so easy to use; It could be used by a oil change guy, a general service tech, a master diagnostic tech, and even the back yard mechanic! This tool is easily one of the most useful in my toolbox.  You wont regret getting one, I sure don't!

Page 4 of 4